A composition is provided, the composition comprising an active compound contained within a microcapsule, the microcapsule having a wall comprising a polyurea formed by a polyisocyanate and a cross linking agent the cross linking agent, being the product of the reaction of a hydroxide salt with the copolymerization product of styrene and maleic anhydride. The active compound may be an agrochemical, in particular a herbicide or an insecticide. A process for the preparation of a microencapsulated active component is also provided, the process comprising: providing an aqueous phase comprising a cross linking agent being the product of the reaction of a hydroxide salt with the copolymerization product of styrene and maleic anhydride； providing a first water- immiscible organic phase comprising an active ingredient to be encapsulated and a first polyisocyanate； dispersing the first organic phase in the aqueous phase； and allowing an interfacial polymerization reaction to occur at the interface of the organic phase and the aqueous phase to form a polyurea shell having the active component encapsulated therein.
